What causes long Covid? New research sheds light on four biological conditions

Four biological factors that can be identified early during a person’s coronavirus infection appear to correlate to the increased risk of long Covid, a new survey has found.

The research, published in the Cell journal, followed over 200 patients for two to three months following their Covid-19 diagnoses to identify the biological factors that might help predict if a person would develop long Covid, The New York Times reported.

There are still many mysteries surrounding long Covid: Who is more prone to it? Are some people more likely to experience physical, cognitive, or neurological symptoms than can linger for months after infections clear?

The researchers said they found that these factors were associated with long Covid (medical name post-acute sequelae of Covid-19, or PASC), whether the initial infection was mild or serious. They said the findings could suggest ways to prevent or treat some long Covid cases, including the possibility of giving antiviral medications soon after infection.

University of California, San Francisco, Professor of Medicine Dr Steven Deeks told The New York Times that this was the first real attempt to come up with biologic mechanisms for long Covid. Dr Deeks was not involved in the study.

Dr Deeks and other experts, however, cautioned that the findings were still exploratory and would need verification with considerably more research.

Among the four factors identified is the coronavirus RNA level in the blood early in the infection, which indicates the viral load. Another factor is the presence of certain autoantibodies — antibodies that mistakenly attack tissues as they do in conditions such as rheumatoid arthritis and lupus.

The third factor identified is the reactivation of Epstein-Barr virus, which infects most people, often at a young age and then becomes dormant.

The final factor is Type 2 diabetes. However, the researchers and experts said studies involving larger numbers of volunteers might reveal that diabetes was only one of several medical conditions increasing the risk of long Covid.